Question

What is the difference between a bus network and a star network?

Short answer

A bus network connects devices to a single central cable, while a star network connects each device to a central hub or switch.

Step-by-step solution

Understand Network topologies

Network topology is the arrangement of different elements (links, nodes) in a computer network. Topologies can define both physical and logical arrangement of a network.

Define Bus Network

A bus network is a network topology in which all devices are connected to a single central cable, known as the bus or backbone. Data sent from a device travels in both directions along the bus until it reaches its destination.

Define Star Network

A star network is a type of network topology where each node (e.g., computer or device) is independently connected to a central device, usually a hub or a switch. Data passing between nodes must go through the central device.

Analyze the Connectivity of Devices

In a bus network, devices share one connection and data travels in both directions along a single bus. In contrast, a star network uses point-to-point connections to a central device, meaning each device has its individual connection.

Consider the Impact on Network Performance

In bus networks, a failure in the bus (central cable) can paralyze the network. Conversely, in a star network, a failure in one connection will only affect that single node, while the rest of the network remains functional.

Evaluate the Scalability and Cable Requirements

Bus networks require less cable than star networks and are easier to set up for small networks, but scalability is limited due to signal degradation over long distances. Star networks, while requiring more cable, offer better scalability and easier maintenance, as nodes can be easily added or removed without affecting others.

Key concepts

bus network

A bus network is one of the simpler forms of network topologies. It relies on a single central cable, called the bus or backbone, to connect all network devices.
As data is sent along this cable, it travels in both directions until it reaches the correct device. When you picture it, think of a single straight line—this line represents the bus.

• All devices in a bus network listen for data meant specifically for them.
• The bus serves as the only communication path.
• If the central bus fails, the entire network is affected.

Bus networks are cost-effective for small setups due to minimal cabling. However, signal degradation is a major concern, especially as the network grows or the bus gets longer.
Another disadvantage is limited scalability, which means adding more devices isn't as straightforward as one might want. When planning for a bus network:

• Consider how signal interference may affect performance.
• Remember that more devices might not always result in better performance.

star network

The star network design is quite different compared to the bus network. Here, each device is independently connected to a central device, such as a hub or switch.
This results in a set of point-to-point connections that originate from and terminate at the central device.

• Data travels from a device to the hub or switch, then to its destination.
• If one connection fails, only that device is affected.
• The central device creates a reliable node for communications.

The star network is highly favored for its robustness. If a connection breaks, only the device linked to that broken connection is affected, leaving the rest of the network operational.
This topology is easily scalable because new devices just need an additional port on the central hub for connection. The need for more cables makes it initially more expensive to set up, but maintenance and upgrades are often simpler and fail-safe. When using a star network:

• Ensure the central device has enough ports for expansion.
• Consider that a failure in the central device can still disable the complete network.

network scalability

Scalability is an important consideration in network design. It refers to a network's ability to grow and handle increased load or changes without sacrificing performance.
When comparing bus and star networks, scalability features prominently in determining which topology better suits long-term needs.

• Bus networks are limited because adding devices can lead to signal issues.
• Star networks thrive with scalability, as new devices add minimal complexity.
• Building in redundancy in a star network can further enhance load management.

Star network topology generally stands out for its scalable nature. As network demands increase, new devices can easily be added by extending connections from the central switch or hub.
The network grows as needed, staying efficient with clear patches for data flow. As you plan for scalability:

• Make sure to have a central device that can handle increased traffic.
• Aim for high-quality cables and connectors to support network extensions.